--- /dev/null
+diff -u -r ../bvi-1.4.0/comm.c ./comm.c
+--- ../bvi-1.4.0/comm.c 2014-01-29 14:54:53.000000000 +0000
++++ ./comm.c 2017-07-07 07:11:55.310380582 +0000
+@@ -84,10 +84,10 @@
+ extern char *name; /* actual filename */
+ extern char **files; /* used for "next" and "rewind" */
+ extern int numfiles, curfile;
+-extern int errno;
+
+ static char oldbuf[CMDSZ]; /** for :!! command **/
+
++int save_chk(char* fname, char* start, char* end, int flags);
+
+ /*
+ * docmdline() - handle a colon command